From my experience (you don't need to follow these) I would say:
Save merch, monetizing, and all that jazz in the back burner. You want to build a fan base and content first--always. Your readership is always your priority, the money will follow eventually. Everything you do is to benefit your readers.
You always want your readers to have that trust in you that you can deliver on a consistent schedule. I suggest to have a buffer of a month or 2, so that way if you get sick or something comes up at least your comic continues to be updated. Take full advantage of the schedule button if possible.
Also like the other replies said, DON'T SPAM! Readers love to see that an actual human being is behind their favorite comic, not a mindless link-posting bot.
Be friendly with other creators and retweet/share their posts, who knows? They may return the favor.
If you can avoid posting negativity. Try to maintain a cheerful persona even if an ostrich who is holding a 10-year grudge against you decided to chase you across town. You keep on smiling!
Upload to different sites such as comicfury.com and webtoons.com
If your comic is good, then you'll get an audience. Like they always say "One is better than none!"
Hope it helps and good luck with your comic!